Japan Castle Explorer: Uchiyama Castle -Castle and commander well served roles-

Uchiyama Castle

-Castle and commander well served roles-

Overview

Name: Uchiyama castle (Uchiyama-jo)
Alias:
Place: Uchiyama Saku city, Nagano
Type: Mountain Castle
Built: 16th century
Remaining remnants: Stone walls, clay walls and moats
Title:

Brief History

Uchiyama castle (内山城) is located over a triangle shaped mountain, one of about 150 meter height from hillside at the edge of ridges spread westward from Kanto mountains. Around Uchiyama castle, Hiraga castle and Shiga castle which are roughly same size exists at 2 kilometer southwest and 2 kilometer north respectively, both at the edge of ridge same as Uchiyama castle.

Tributaries of Chikuma-gawa rivers which flow from Kanto mountains eastward to Chikuma-gawa river in the east part of Saku city were not only the living space of people but also the route toward Kozuke province (Gunma prefecture). Especially the valley of Uchiyama-gawa river runs straightly toward the border and could cross Uchiyama-Toge pass relatively easy toward Shimonita area.

Due to this good condition, this Uchiyama-Toge route of Shimonita-Kaido road was treated as a bypass route of Nakasendo Road which passes Usui-Toge pass in Edo era. Relatively gentle slope of the road was suitable for female travelers, and also the transportation of materials such as rice, raw silk, tobacco or lacquered items. In medieval era, this condition was also suitable for the march of army, and Uchiyama castle existed just at the entrance of Uchiyama valley.

Origin of Uchiyama castle

Precise year is unknown but Uchiyama castle might be built by local lord Oi clan in the beginning of 16th century. Oi clan was a tributary of Ogasawara clan, a traditional family of Minamoto clan and served the governor of Shinano province (Nagano prefecture). Oi clan diverged from Ogasawara clan in 13th century but cooperatively acted with it and grew at Saku providence in 14th century.

Oi clan originally resided at Iwamurada area near Uchiyama castle, but in the former half of 15th century Oi clan fought with Ashida clan, the local lord of current Tateshina town at the west of Saku area. The territory of Oi clan expanded to the south part of current Ueda city, where is connected to Matsumoto area or Suwa area.

But in the latter half of 15th century, Oi clan declined its power by the failure of attack to Takeda clan, the governor of Kai province (Yamanashi prefecture) which was in trouble at that time. Takeda clan quitted trouble reversely attacked Oi clan, then in 1479 Oi clan suffered severe defeat before neighbor lord Tomono clan.

Advance of Takeda clan to Saku providence

Furthermore in 1483, Oi clan was attacked by Murakami clan, the strong local lord of Kazurao castle near Ueda city. Oi castle, the main base of Oi clan fell and the main stream of Oi clan ended its history, but branch family of Oi clan still remained and Oi clan was succeeded by Nagakubo clan, the branch family at western edge of territory.

In the beginning of 16th century Takeda clan fell into severe internal conflict, but by around 1520 Nobutora Takeda (1474-1574), the father of Shingen Takeda (1521-1583), united Kai province breaking his opponents. Nobutora who united Kai province next started aggressive attack to Shinano province (Nagano prefecture), under alliance with Suwa clan at Suwa basin.

In 1540, Nobutora Takeda and Suwa clan intruded into Shinano province and captured Nagakubo castle (Nagano prefecture), which was protected by Sadataka Oi (?-?), the leader of Oi clan and elder brother of Sadakiyo Oi (?-1575) who was the lord of Uchiyama castle. Suwa clan once seized Nagakubo castle but Sadataka Oi once left the castle and waited opportunity.

Capture by Takeda clan

In 1541, Nobutora Takeda, Suwa clan and Yoshikiyo Murakami (1501-1573) cooperatively attacked Unno clan and their relatives at the battle of Unnodaira. Unno clan including Sanada clan left Shinano province, and participants divided captured territory. But after this battle, Shingen Takeda expelled his father Nobutora Takeda and became new leader of Takeda clan.

After succession Shingen Takeda broke the treaty with Suwa clan, and ruined Suwa clan in 1542. Next year in 1543 Shingen attacked Nagakubo castle once Sadataka Oi returned, then Nagakubo castle fell again and Shingen used this castle as his bridgehead to proceed to Chiisagata providence and Saku providence.

After that Shingen attacked south part of Shinano province such as Takato castle (Nagano prefecture), then returned to Saku providence. In 1547, Shingen attacked Uchiyama castle, and Sadakiyo Oi resisted two weeks against Takeda army but finally opened the castle.

Usage as local military base

Next year Shingen attacked Shiga castle (Nagano prefecture) just at the north of Uchiyama castle, and finally fell it breaking resistance of its lord Kiyoshige Kasahara (1515-1547) and reinforcement army from Yamanouchi Uesugi clan which was the warlord of Kozuke province (Gunma prefecture). By fall of Shiga castle Shingen captured whole part of Saku providence but also had to prepare for Kozuke province.

As a defense line toward Kozuke province, Shingen used all of Uchiyama castle, Shiga castle and Hiraga castle at neighbor place. But Uchiyama castle was used as a main base of Takeda clan, as Hiraga castle was at gentle slope and difficult to defend, and Shiga castle was at narrow ridge and limited room for expansion. Of all Shiga castle had an image of tragic end of Shiga clan and it might attract antipathy of local residents.

Contrary to this, Uchiyama castle is a bit smaller but had a room for expansion and could control the road to Kozuke province. Shingen Takeda reformed Uchiyama castle as a core military base of Takeda army of the area. Shingen placed his confident general Toramitsu Oyamada (?-1579) as a commander of the castle.

Structure of Uchiyama castle

Uchiyama castle spreads over triangle shaped mountain with three ridges. Hilltop area consists of oblong shaped central area and secondary area totally 50 meter long and 20 meter wide, and attached terrace at north and south of core areas. Northeast ridge which is connected to backside mountains is securely protected by layer of terraces and dry moat.

At the west ridge, layer of terraces are built over sheer slope from hilltop to hillside. The highest terrace is protected by low height stone wall and might be used as entrance area. Below of the terraces there is a flat space of Kinugasa Shrine which might be used as a ground of the residence of the lord.

At south of central area, below of huge rock there is a large Baba area which is about 50 meter long, but the traverse route to this part is closed and not accessible. Ahead of northwestern ridge there is also a terrace but this area is also not accessible due to sheer slope and bush. Total length of castle is about 400 meter long, and layers of terraces at western slope might be brought by Takeda clan.

Confident veteran general of Takeda army

Toramitsu Oyamada, the commander of Uchiyama castle, was originally named as Iganokami Uehara. Toramitsu was originally a retainer of Nobukata Itagaki (1489-1548), the highest retainer of Shingen Takeda at first period. Later Shingen promoted Toramitsu as the commander of captured Uchiyama castle, where was necessary to cope with non obedient local lords and external powers.

As expected, Uchiyama castle was attacked by Yamanouchi Uesugi clan or Yoshikiyo Murakami both once held Saku province, but Toramitsu well protected it and stood until the arrival reinforcement army from Shingen. This prevented the collapse of defense line of Takeda clan in Saku area and prepared counter attack to both parties.

After the capture of Saku providence Shingen Takeda attacked Yoshikiyo Murakami, and being broken two times at the battle of Uedahara and siege of Toishi castle (Nagano prefecture) Shingen finally captured Kazurao castle in 1553 and expelled Yoshikiyo to Echigo province (Niigata prefecture).

Hard work at front line castles

As a commander of next area of Murakami territory, Torashige Oyamada was on the frontline against Murakami clan. Furthermore, Toramitsu commanded Yukitaka Sanada (1513-1574), who fell Toishi castle by his plot in 1551. Toramitsu faced against brave Yoshikiyo Murakami well and contributed to ruin of Murakami clan.

After the fall of Murakami clan, Shingen Takeda entered into the confrontation of Kenshin Uesugi (1530-1578), the warlord of Echigo province and who supported Yoshikiyo Murakami. Shingen and Kenshin fought at Kawanakajima area of current Nagano city intermittently for 10 years, and Torashige served as the commander of Amakazari castle, the bridgehead of Takeda army at Kawanakajima area.

Subsequent to the battle of Kawanakajima, Takeda clan turned its army to Kozuke province. Due to the location next to Kozuke province, Torashige engaged in the attack to Kozuke province and served as the commander of Matsuida castle (Gunma prefecture), an important border castle.

Leave way to next generation

In 1560’s, next generation such as Masakage Yamagata (1515?-1575) or Nobufusa Baba (1515?-1575) later praised as four excellent generals of Takeda army stood out and were appointed as the commander of forefront castles. The role of Toramitsu changed to support for such younger generals, and Uchiyama castle was no more forefront castle due to further expansion of Takeda clan.

After the death of Nobukata Itagaki and Torayasu Amari (1498-1548) at the battle of Uedahara, Torayasu Oyamada well worked as the commander of forefront castle and contributed to the change of Takeda clan from small local lord to large warlord. Uchiyama castle also fulfilled its duty as the bridgehead toward Kawanakajima area and Kozuke province.

Toramitsu Oyamada served as the commander of Uchiyama castle until his death in ill in 1579, three year before the fall of Takeda clan. His son Masayuki Oyamada (?-1582) succeeded the position of Toramitsu Oyamada as the commander of Uchiyama castle, but in 1582 Masayuki and his younger brother Daigakunosuke Oyamada (?-1582) fought against Oda army at Takato castle (Nagano prefecture) and died.

Afterward of castle

After the fall of Takeda clan and death of central ruler Nobunaga Oda (1534-1582) who ruined Takeda clan in the incident of Honnoji in 1582, Hojo clan which was the warlord of Sagami province (Kanagawa prefecture) and once place Kuninori Inomata (?-1590), who was famous for the capture of Nagurumi castle (Gunma prefecture) in 1589.

But soon Nobushige Yoda (1548-1583) who was the lord of neighbor Ashida castle (Nagano prefecture) fell it under the support of Ieyasu Tokugawa (1543-1616), the warlord of Mikawa province (east half of Aichi prefecture) and fought for Shinano province against Hojo army. After the treaty between Hojo clan and Tokugawa clan Uchiyama castle was abolished.

Now no building remains but structure of the castle well remain on the mountain. The mountain is not so high but covered with layers of terraces, and seems impregnable even though having no latest defense structure. The shape of the castle is looks like a veteran commander who is not as famous as four excellent generals but well served its role and handed it to next generation.

Access

30 minutes drive from Joshinetsu Jidoshado Expressway Saku interchange to parking of Onjo-ji temple. Entrance of climbing road is at side of Onjo-ji temple. Be careful as climbing road is covered by bamboos.